Front rower Afoa suffered a suffered a dislocated elbow and Harris a knee injury in the team's loss to Cronulla last round.
Afoa is expected to be sidelined for six weeks while the recovery for second-rower Harris is four-to-six weeks, depending on how he comes through surgery.
There are several changes for the side this round with Simon Mannering moving from loose forward to the second row to replace Harris while Adam Blair makes a timely return from a one-match suspension to reclaim the No 13 jersey.
